//input[type=checkbox] 美化
    .u-inp-chkbox-bt {
      position: absolute;
      left: -9999px;
    }

    .u-label-bt {
      display: inline-block;
      position: relative;
      width: 40px;
      padding: 10px 15px;
      box-sizing: border-box;
      border: 2px solid #fff;
      border-radius: 100px;
      color: #fff;
      background-color: #6a8494;
      box-shadow: 0 0 10px rgba(0, 0, 0, .2);
      white-space: nowrap;
      cursor: pointer;
      user-select: none;
      transition: background-color .2s, box-shadow .2s;
    }
    .u-label-bt::before {
      content: '';
      display: block;
      position: absolute;
      top: -1px;
      bottom: 10px;
      left: -1px;
      width: 22px;
      height: 22px;
      box-sizing: border-box;
      border: 3px solid #fff;
      background: #fff;
      border-radius: 100px;
      transform: translateX(0);
      transition: background-color .2s ,transform .2s;
    }
    .u-label-bt:hover,
    .u-inp-chkbox-bt:focus+label {
      
      box-shadow: 0 0 5px rgba(0, 0, 0, .6);
    }
    .u-inp-chkbox-bt:checked+.u-label-bt {
      background-color: #3dba3f;
    }
    .u-inp-chkbox-bt:checked+.u-label-bt::before {
      background-color: #fff;
      transform: translateX(17px);
    }